Posted by Tom Napier on April 13, 2010 at 09:46:06 user Didymus.
In Reply to: Re: "pull left" and other puzzlements... posted by Jon on April 13, 2010 at 06:16:33:
It is worth remembering that in the early years of Morse telegraphy all communication was by a tap code. The receiving device was a "sounder" whose armature was pulled down when the transmitting key was pressed and which sprang back when the key was released. A dot was "click-clack" and a dash was "click - - - clack." A later development was the fitting of a pen to the armature to make dots and dashes on a moving strip of paper.
The conventional dot and dash sound dates from around 1900 when radio-telegraphy started.